Use a different button type

src/Bundle/ChillCalendarBundle/Resources/views/Calendar/_list.html.twig

@@ -221,7 +221,7 @@
                         </li>
                         <li>
                             <a href="{{ chill_path_add_return_path('chill_calendar_calendar_cancel', { 'id': calendar.id } ) }}"
-                               class="btn btn-delete">{{ 'cancel'|trans }}</a>
+                               class="btn btn-remove">{{ 'cancel'|trans }}</a>
                         </li>
                         {% endif %}